Clem said Thursday that he had raised $100,000 to buy the storied but vacant rooming house on Zack Street. But he said a real estate closing scheduled for Monday fell through because the city made "outrageous demands I can't meet."

The city said it proposed a timetable giving Clem six months, with interim deadlines for specific tasks, after his team asked for more time. He said the idea of engaging a contractor by Feb. 3 and paying $8,700 in code enforcement fines were nonstarters.

Saving the Jackson House "was going to cost them nothing except a little patience and to work with me a little bit and not treat me like some schlep," he said during his show on 102.5 FM. "It's a personal vendetta."

Not that Clem wants to make peace with Mayor Bob Buckhorn.

"I will be a thorn in his side until he runs for re-election," said Clem, adding, "I might run for mayor" against Buckhorn in 2015.

Buckhorn declined to comment. His spokeswoman said he had better things to do than take part in a publicity stunt. And the city attorney described Clem's narrative as inaccurate, disingenuous and unfair.

"We were being more than generous," City Attorney Julia Mandell said. "We've never not been willing to work with them, but it's hard to work with someone who won't tell you where they're at or what they want to accomplish other than, 'We need more time.' "

The 24-room Jackson House is on the National Register of Historic Places and Florida's Black Heritage Trail. During segregation, it welcomed guests like Billie Holiday, Ella Fitzgerald, Nat "King" Cole, James Brown and the Rev. Martin Luther King Jr.

But it needs an estimated $1.5 million in repairs. A community group led by Hillsborough County Tax Collector Doug Belden concluded in October that it was beyond saving. The foundation needs shoring up, the wiring is outdated and the plumbing is shot. There's wood rot, asbestos and lead paint, plus a hole in the roof and a two-story addition in danger of collapse.

For months, city officials have said the building is a risk to public safety, so it must be secured and stabilized — and soon — or it will have to come down.

The city gave owner Willie Robinson Jr. a deadline of Nov. 30 to fence and insure the house, as well as come up with a stabilization plan ready for permitting.

After Robinson said he couldn't do that, Clem said his charitable foundation would buy the building and rallied listeners to help.

On Thursday, Clem said he had lined up 100 volunteers in the building trades, including professionals like "structural engineers." He also said he believed the $1.5 million repair cost was "highly inflated."

On Dec. 23, the city issued Robinson an order to stabilize the house by March 1.

That, Mandell said, is the timetable the city had in place until late Monday — the day of the closing.

Late Monday, she said, Clem's team said it needed six months to stabilize the building and two years to bring it into compliance with city codes.

In response, Mandell said the city sent Clem's team a draft of an amended order to stabilize the building by July 1. Specifically, the draft — which Mandell described as a proposal for discussion — would have required Clem to:

• Engage a general contractor by Feb. 3.

• Secure permits for stabilization and roof repair by March 3. That work would have to be 75 percent done by June 2.

Failure to meet the milestones could have led to an order to demolish, the draft said.

Ridiculous, Clem said.

"How can I pick a (general contractor) in two weeks?" he said. "Have him vetted? Have him bamboozled into doing it for free?"

The timetable also seemed like a sudden change to preservationists working with Clem's team.

"I am sick at heart," said former City Council member Linda Saul-Sena, who has worked for months to save the Jackson House. "I am very, very frustrated that the administration put these roadblocks up at the absolute 11th hour."

This is not the first time Clem has taken to the air to criticize Buckhorn. In late 2012, he vowed to "make it my mission to destroy" the mayor.

That was in response to news that Buckhorn had written in an email, "this Bubba the Love Sponge is a complete moron." The remark referred to Clem's plan in early 2012 to "deep fat fry" the Koran because Muslims were outraged that American troops in Afghanistan had burned the holy book. Clem's Koran-frying never took place.

While he has given up on saving the Jackson House, Clem promised that Robinson would not get stuck with demolition costs and fines that deplete his equity in the property.

"My investors are going to give Willie $100,000 and pay for all demolition and fines," Clem said. That check, he said, should be issued in 10 to 14 days.